Current Research & Publications

Research into the breeds that are affected and which drugs cause
problems for dogs that have the MDR1 mutation is still in progress at
the Washington State University College of Veterinary Medicine. We are
looking at other breeds to see if they have the mutation and taking
reports by owners and veterinarians on other drugs that may cause
problems for these dogs.

We are currently seeking samples from dogs of the herding breeds
(Collies, Australian Shepherds, etc.) that have experienced unexpected
reactions to drugs when administered at normal doses.

We are also working with veterinarians in Australia and France to
determine the frequency of the mutation in herding breeds in those
countries. Results of these tests are expected this year.

We are looking ahead to three important research directions

We'd like to expand our research to identify other dog breeds that
experience a high incidence of adverse drug reactions.

We believe there may be other chemicals and drugs that may cause
problems through this system or similar gene mutations. We'd like to
further define which chemicals and drugs those are.

A key problem with getting needed drugs into the brain and keeping
them there is the very system that we discovered through our study of
the MDR1 gene mutation. Could this gene or others be exploited when
needed to ensure that we can get vital chemotherapeutic drugs into the
brain and hold them there? Further studies by our research group may
answer that question and provide a less toxic, more effective way to
treat cancers or diseases of the brain.

Mealey KL, Bentjen SA, Waiting D. Frequency of the mutant MDR1 allele associated
with ivermectin sensitivity in a sample population of Collies from the
northwestern United States. American Journal of Veterinary Research,
2002;63:479-481.